A:
Positive:
1 x 287206155 x 57441237 x 410294511 x 261096535 x 82058949 x 58613555 x 52219377 x 372995245 x 117227385 x 74599539 x 532852695 x 10657
Negative:
-1 x -28720615-5 x -5744123-7 x -4102945-11 x -2610965-35 x -820589-49 x -586135-55 x -522193-77 x -372995-245 x -117227-385 x -74599-539 x -53285-2695 x -10657
Unfortunately, there's not simple formula to identifying all of the factors of a number and it can be a tedious process when trying to identify the divisors of larger numbers. To find the factor combinations of the number 28,720,615, it is easier to work with a table - it's called factoring from the outside in.
We start by creating a table and writing 1 on the left side and then the number we're trying to find the factors for on the right side in a table. Then, below that, write the numbers as a negative as well.
| 1 | 28,720,615 | |
| -1 | -28,720,615 |
When you multiply two negative numbers together, you get a positive number. That means both the positive and negative numbers are factors of 28,720,615.
Example:
1 x 28,720,615 = 28,720,615
and
-1 x -28,720,615 = 28,720,615
Notice both answers equal 28,720,615
With that explanation out of the way, let's continue. Next, we take the number 28,720,615 and divide it by 2:
28,720,615 ÷ 2 = 14,360,307.5
If the quotient is a whole number, then 2 and 14,360,307.5 are factors. In this case, the quotient is not a whole number. Don't write anything down and try the next divisor.
Here is what our table should look like at this step:
| 1 | 28,720,615 | |
| -1 | -28,720,615 |
Now, we try dividing 28,720,615 by 3:
28,720,615 ÷ 3 = 9,573,538.3333
If the quotient is a whole number, then 3 and 9,573,538.3333 are factors. In this case, the quotient is not a whole number. Don't write anything down and try the next divisor.
Here is what our table should look like at this step:
| 1 | 28,720,615 | |
| -1 | -28,720,615 |
Let's try dividing by 4:
28,720,615 ÷ 4 = 7,180,153.75
If the quotient is a whole number, then 4 and 7,180,153.75 are factors. In this case, the quotient is not a whole number. Don't write anything down and try the next divisor.
Here is what our table should look like at this step:
| 1 | 28,720,615 | |
| -1 | 28,720,615 |
If you did it right, you will end up with this table:
| 1 | 5 | 7 | 11 | 35 | 49 | 55 | 77 | 245 | 385 | 539 | 2,695 | 10,657 | 53,285 | 74,599 | 117,227 | 372,995 | 522,193 | 586,135 | 820,589 | 2,610,965 | 4,102,945 | 5,744,123 | 28,720,615 |
| -1 | -5 | -7 | -11 | -35 | -49 | -55 | -77 | -245 | -385 | -539 | -2,695 | -10,657 | -53,285 | -74,599 | -117,227 | -372,995 | -522,193 | -586,135 | -820,589 | -2,610,965 | -4,102,945 | -5,744,123 | -28,720,615 |
Here are some more numbers to try:
Try the factor calculator